<html>
 <head>
  <link href="./leetcode-problem.css" rel="stylesheet" type="text/css">
 </head>
 <body>
  <div class="question_difficulty">
   难度：Hard
  </div>
  <div>
   <h1 class="question_title">
    76. Minimum Window Substring
   </h1>
   <p>
    Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).
   </p>
   <p>
    <strong>
     Example:
    </strong>
   </p>
   <pre>
<strong>Input: S</strong> = "ADOBECODEBANC", <strong>T</strong> = "ABC"
<strong>Output:</strong> "BANC"
</pre>
   <p>
    <strong>
     Note:
    </strong>
   </p>
   <ul>
    <li>
     If there is no such window in S that covers all characters in T, return the empty string
     <code>
      ""
     </code>
     .
    </li>
    <li>
     If there is such window, you are guaranteed that there will always be only one unique minimum window in S.
    </li>
   </ul>
  </div>
  <div>
   <h1 class="question_title">
    76. 最小覆盖子串
   </h1>
   <p>
    给定一个字符串 S 和一个字符串 T，请在 S 中找出包含 T 所有字母的最小子串。
   </p>
   <p>
    <strong>
     示例：
    </strong>
   </p>
   <pre><strong>输入: S</strong> = "ADOBECODEBANC", <strong>T</strong> = "ABC"
<strong>输出:</strong> "BANC"</pre>
   <p>
    <strong>
     说明：
    </strong>
   </p>
   <ul>
    <li>
     如果 S 中不存这样的子串，则返回空字符串
     <code>
      ""
     </code>
     。
    </li>
    <li>
     如果 S 中存在这样的子串，我们保证它是唯一的答案。
    </li>
   </ul>
  </div>
 </body>
</html>